(1) Field of the Invention
The present invention relates to a novel 2-substituted-4,6-diamino-s-triazine/isocyanuric acid adduct (hereinafter referred to as "adduct"), a process for the synthesis of this adduct and a process for curing a polyepoxy resin with this adduct.
Since an epoxy resin cured by using the adduct of the present invention exerts a prominent effect of preventing the migration of metals forming a wiring circuit, such as gold, silver and copper, it is expected that the present invention is especially valuable in the fields of the production of sealing materials for electronic parts, copper-lined laminates and coating materials for organic and inorganic substrates.
(2) Description of the Prior Art
Epoxy resins have been widely used as sealing materials, insulating materials and matrix materials for substrates in the fields of electronic parts and printed circuit boards, because they are excellent in the heat resistance, electrically insulating property and adhesiveness.
However, epoxy resins are poor in the function of preventing the migration, that is, the phenomenon in which a metal constituting a wire or electrode on an insulating material is caused to migrate on the insulating material by the potential difference in a high-humidity atmosphere, and therefore, such troubles as insufficient insulation and formation of short circuits readily occur.
With recent reduction of the size and recent increase of the density in electronic parts and also with recent desire to make wiring circuits finer, the requirement for preventing the migration becomes severe.
Various commercially available migration-preventing resins are still insufficient because curing conditions are severe, the shrinkage by curing is extreme or the adhesiveness is low.
Glass frits used for ceramic substrates have an excellent migration-preventing effect, but they are defective in that they are expensive and the baking temperature is high.